Adam Riess of Johns Hopkins University is one of three researchers just awarded the Nobel Prize for Physics for their part in the discovery that the expansion of the universe is accelerating. In 2009, Gregg Easterbrook of The Atlantic interviewed Riess about
his work on galactic expansion. Here Easterbrook looks back on that meeting.

In the 1920s, Edwin Hubble showed that the universe, thought since the Greeks to be changeless, instead is expanding. But at what rate? Some
theoreticians predicted the expansion, driven by the momentum of the Big Bang, should be slowing. Eventually the galaxies would either stop their
outward travel and the cosmos become static, or gravity would pull everything back together for a Big Crunch. Other theoreticians felt cosmic expansion
would continue at a steady pace essentially forever. Since the galaxies must long ago have overcome the gravity of the Big Bang in order to be rushing
outward, this reasoning went, they'll simply keep going.

Numerous attempts were made to measure the movements of distant galaxies, in order to estimate whether the expansion is steady or slowing. In the
mid-1990s, a team led by Adam Riess of Johns Hopkins employed images of very distant supernovae to derive what was considered the most accurate
measurement to date of cosmic speed. The researchers reviewed their data many times, always coming to the same vexing conclusion: the expansion of the
universe is speeding up.

Riess and his associates found that for the last 7 billion years or so -- roughly the halfway point of the apparent lifetime of the cosmos - galactic
expansion has been gaining speed. This would be possible only if something is pushing the galaxies, adding energy to them. So Riess posited "dark
energy," a force that is real but eludes detection.

A quick trip to the blackboard for calculations showed that in order for the galaxies to be accelerating in their observed manner, three-quarters of
the universe must be dark energy, while a mere fraction of the content of the universe is the "ordinary" matter and energy that's found in our solar
system. But though Riess is a founder of the dark energy concept, he says, "I have absolutely no clue what dark energy is." Dark energy appears strong
enough to push the entire universe - yet its source is unknown, its location is unknown and its physics are highly speculative.

The whole dark-energy concept is so strange, so utterly lacking antecedent either in theory or in common-sense experience, it was as if someone walked
up and said, "Hey, did you hear Britney Spears just found the cure for cancer?"

For a century, physicists have elaborately fine-tuned a concept of the natural world in which there are four fundamental forces: gravity, the "strong
force" that holds atoms together, the "weak force" that keeps electrons in place around atoms, and electromagnetism (light, radio waves, X-rays, etc.).
Entire academic careers have been made on work refining four-forces thinking. Suddenly there's a fifth force, dark energy. And although it appears to
comprise three-quarters of the universe, nobody's noticed it till now.

Gravity is inverse to distance, meaning as objects draw close together the attraction becomes more powerful; as they move apart, fades significantly.
Dark energy appears to operate the other way around, proportional to distance: feeble between objects close by, steadily stronger as objects get
farther apart.

"Dark energy is incredibly strange, but actually it makes sense to me that it went unnoticed, because dark energy has no effect on daily life, or even
inside our solar system," Riess says. "We know there is gravity because apples fall from trees. We can observe gravity in daily life. If we could throw
an apple to the edge of the universe, we would observe it accelerating. Until the 1990s, there were few reliable observations about movement at the
scale of the entire universe, which is the only scale dark energy effects. So dark energy could not be seen until we could measure things very, very
far away."

Unable to explain why the universe had not folded back onto itself as his General Theory of Relativity seemed to suggest should have occurred, Albert
Einstein inserted an anti-gravity term into his equations -- the "cosmological constant," a hypothetical force that pushed outward on creation. Later
Einstein retracted the idea, admitting there was no evidence for a cosmological constant nor any physical explanation of how one might function. Now
there does seem to be a repulsive force, dark energy, whose role is similar to Einstein's conjecture.

And dark energy is - what, exactly?

Physicists use the paradoxical term "vacuum density." Occasionally in vacuum-chamber experiments, subatomic particles swirl in and out of existence,
seeming to come from nowhere and return to nowhere. It does not appear to be possible to make a vacuum in which there is nothing at all, so it is now
assumed that intergalactic space is not a true void. Perhaps the interstellar void contains both ghost particles and energy potential, the latter of
which is expressing itself by causing cosmic acceleration.

That vacuum could be the source of energy appears to make no sense: but also appears to be what's happening. Because space keeps expanding, every day
there is more vacuum, which would mean every day there is more vacuum-produced dark energy. At the Big Bang, dark energy was a trivial constituent of
the cosmos; now it's 74 percent of creation and growing. An eon from now, the universe might be 99 percent dark energy, with the galaxies expanding
away from each other at unfathomable speeds .

Here is a spooky thought. Physicist Lawrence Krauss of Arizona State University calculates that three trillions years from now -- about the time the
federal budget is expected to be balanced -- dark energy will have accelerated the universe to such speeds that no galaxy will be able to see any other
galaxy. Intercourse between galaxies will become unimaginable, even if Captain Kirk's warpdrive is invented. Each galaxy will perceive itself as the
whole of creation, a lonely cluster of stars surrounded by infinite emptiness. At this far-future point, all traces of the Big Bang will have
dissipated from the cosmos. Any intelligent beings evolving under those circumstances would not be able to figure out how the universe formed. We're
lucky, Krauss thinks, to have come into existence while the cosmos is "young," and dark energy has not yet hurled away all the clues about why we are
here.

Of course there may also be some force or factor at work that no one has yet guessed. Perhaps our descendents will say, "Can you believe that in the 21st century, Nobel Prize winners thought the entire universe could be pushed by an invisible unknown force no one can locate? And Atlantic writers fell for it!"

For today, Adam Riess of Johns Hopkins, Saul Perlmutter of Cal Berkeley and Brian Schmidt of Australian National University are the state of the cosmic
art.

Most Popular

After a year of uncertainty and unhappiness, the president is reportedly feeling more comfortable—but has he really mastered the job?

It was a fun weekend for Donald Trump. Late on Friday, Attorney General Jeff Sessions fired Andrew McCabe, the outgoing FBI deputy director whom Trump had long targeted, and the president spent the rest of the weekend taking victory laps: cheering McCabe’s departure, taking shots at his former boss and mentor James Comey, and renewing his barrage against Special Counsel Robert Mueller.

Trump’s moods shift quickly, but over the last week or so, a different overarching feel has manifested itself, a meta-mood. Although he remains irritated by Mueller and any number of other things, Trump seems to be relishing the latest sound of chaos, “leaning into the maelstrom,” as McKay Coppins put it Friday. This is rooted, Maggie Haberman reports, in a growing confidence on the president’s part: “A dozen people close to Mr. Trump or the White House, including current and former aides and longtime friends, described him as newly emboldened to say what he really feels and to ignore the cautions of those around him.”

How evangelicals, once culturally confident, became an anxious minority seeking political protection from the least traditionally religious president in living memory

One of the most extraordinary things about our current politics—really, one of the most extraordinary developments of recent political history—is the loyal adherence of religious conservatives to Donald Trump. The president won four-fifths of the votes of white evangelical Christians. This was a higher level of support than either Ronald Reagan or George W. Bush, an outspoken evangelical himself, ever received.

Trump’s background and beliefs could hardly be more incompatible with traditional Christian models of life and leadership. Trump’s past political stances (he once supported the right to partial-birth abortion), his character (he has bragged about sexually assaulting women), and even his language (he introduced the words pussy and shithole into presidential discourse) would more naturally lead religious conservatives toward exorcism than alliance. This is a man who has cruelly publicized his infidelities, made disturbing sexual comments about his elder daughter, and boasted about the size of his penis on the debate stage. His lawyer reportedly arranged a $130,000 payment to a porn star to dissuade her from disclosing an alleged affair. Yet religious conservatives who once blanched at PG-13 public standards now yawn at such NC-17 maneuvers. We are a long way from The Book of Virtues.

Invented centuries ago in France, the bidet has never taken off in the States. That might be changing.

“It’s been completely Americanized!” my host declares proudly. “The bidet is gone!” In my time as a travel editor, this scenario has become common when touring improvements to hotels and resorts around the world. My heart sinks when I hear it. To me, this doesn’t feel like progress, but prejudice.

Americans seem especially baffled by these basins. Even seasoned American travelers are unsure of their purpose: One globe-trotter asked me, “Why do the bathrooms in this hotel have both toilets and urinals?” And even if they understand the bidet’s function, Americans often fail to see its appeal. Attempts to popularize the bidet in the United States have failed before, but recent efforts continue—and perhaps they might even succeed in bringing this Old World device to new backsides.

A new six-part Netflix documentary is a stunning dive into a utopian religious community in Oregon that descended into darkness.

To describe Wild Wild Country as jaw-dropping is to understate the number of times my mouth gaped while watching the series, a six-part Netflix documentary about a religious community in Oregon in the 1980s. It’s ostensibly the story of how a group led by the dynamic Bhagwan Shree Rajneesh purchased 64,000 acres of land in central Oregon in a bid to build its own utopian city. But, as the series immediately reveals, the narrative becomes darker and stranger than you might ever imagine. It’s a tale that mines the weirdness of the counterculture in the ’70s and ’80s, the age-old conflict between rural Americans and free love–preaching cityfolk, and the emotional vacuum that compels people to interpret a bearded mystic as something akin to a god.

Among the more practical advice that can be offered to international travelers is wisdom of the bathroom. So let me say, as someone who recently returned from China, that you should be prepared to one, carry your own toilet paper and two, practice your squat.

I do not mean those goofy chairless sits you see at the gym. No, toned glutes will not save you here. I mean the deep squat, where you plop your butt down as far as it can go while staying aloft and balanced on the heels. This position—in contrast to deep squatting on your toes as most Americans naturally attempt instead—is so stable that people in China can hold it for minutes and perhaps even hours ...

The first female speaker of the House has become the most effec­tive congressional leader of modern times—and, not coinciden­tally, the most vilified.

Last May, TheWashington Post’s James Hohmann noted “an uncovered dynamic” that helped explain the GOP’s failure to repeal Obamacare. Three current Democratic House members had opposed the Affordable Care Act when it first passed. Twelve Democratic House members represent districts that Donald Trump won. Yet none voted for repeal. The “uncovered dynamic,” Hohmann suggested, was Nancy Pelosi’s skill at keeping her party in line.

She’s been keeping it in line for more than a decade. In 2005, George W. Bush launched his second presidential term with an aggressive push to partially privatize Social Security. For nine months, Republicans demanded that Democrats admit the retirement system was in crisis and offer their own program to change it. Pelosi refused. Democratic members of Congress hosted more than 1,000 town-hall meetings to rally opposition to privatization. That fall, Republicans backed down, and Bush’s second term never recovered.

As the Trump presidency approaches a troubling tipping point, it’s time to find the right term for what’s happening to democracy.

Here is something that, even on its own, is astonishing: The president of the United States demanded the firing of the former FBI deputy director, a career civil servant, after tormenting him both publicly and privately—and it worked.

The American public still doesn’t know in any detail what Andrew McCabe, who was dismissed late Friday night, is supposed to have done. But citizens can see exactly what Donald Trump did to McCabe. And the president’s actions are corroding the independence that a healthy constitutional democracy needs in its law enforcement and intelligence apparatus.

McCabe’s firing is part of a pattern. It follows the summary removal of the previous FBI director and comes amid Trump’s repeated threats to fire the attorney general, the deputy attorney, and the special counsel who is investigating him and his associates. McCabe’s ouster unfolded against a chaotic political backdrop that includes Trump’s repeated calls for investigations of his political opponents, demands of loyalty from senior law-enforcement officials, and declarations that the job of those officials is to protect him from investigation.

Middle-class African American families aren’t spending as much on groceries as white families, and the reason isn’t a lack of money, but a lack of options.

Rich Americans spend their money differently than poor Americans—no great surprise there. But the differences in how families spend go beyond earnings. For instance, rich white families spend more on entertainment and groceries than rich black families. And black families at all income levels spend more on things that require a long-term contract, such as electricity and heating services, than white families at corresponding income levels.

These discrepancies illustrate an under-recognized aspect of racial inequality: Blacks don’t just tend to earn less than whites. Even when they earn as much, they seem to still have less access to goods and services than their white peers do.

That’s the finding of a paper by the sociologists Raphaël Charron-Chénier, Joshua J. Fink, and Lisa A. Keister of Duke University, who used data from the Consumer Expenditure Survey to assess the spending habits of white and black households in 2013 and 2014. They argue that access to credit, retail deserts, and discrimination could be major factors in why blacks spend less, in aggregate, than whites. Only one of these challenges—access to credit—is mitigated when black families earn more money.

Days before the 1960 election, Coretta Scott King received a call from then-candidate John F. Kennedy while her husband was in a Georgia jail, charged with trespassing after leading a sit-in demonstration against segregation in Atlanta. “This must be pretty hard on you, and I want to let you both know that I’m thinking about you and will do all I can to help,” Kennedy told her. The Democratic nominee’s brother and campaign manager, Robert Kennedy, called a DeKalb County Judge and successfully lobbied for Martin Luther King Jr.’s release.

The personal call and the timely intervention significantly bolstered Kennedy’s standing among black voters. They also strengthened the political alliance between the Democratic Party and African Americans. After his release, King praised Kennedy for exhibiting “moral courage of a high order.” His father, the influential Baptist pastor Martin Luther King Sr., said, “Kennedy can be my president, Catholic or whatever he is. I’ve got all my votes and I’ve got a suitcase and I’m going to take them up there and dump them in his lap.” Kennedy earned 68 percent of the black vote, which was the decisive factor in key states like Illinois, Michigan, and South Carolina.